A study of the court backlogs by the Institute of Government, a think tank, projected that cutting jury trials would save less than 2% of court time, assuming that the cases would be dealt with more quickly.
Research carried out by Lammy in 2017, before he was a minister, revealed that juries were particularly trusted by ethnic minority defendants.
He says many comparable criminal justice systems, including Canada’s, have introduced similar reforms to speed up justice with no loss of confidence in the courts.
The Ministry of Justice said that more than 90% of criminal cases were already heard fairly without a jury.
A spokesman said: “With victims facing unacceptably long waits for justice after years of delays in our courts, we make no apologies for pressing ahead with our plans to reform the system based on Sir Brian Leveson’s independent review, alongside modernising it for the 21st Century with record investment.”